Microchip detects eye infections in minutes

Clinicians have developed a microchip capable of detecting within minutes sight-threatening eye infections including those caught while wearing contact lenses.

The prototype device is able to measure the properties of a single bacteria such as Escherichia coli and pseudomonas at high speed, removing the need to grow cultures in the laboratory or use antibiotic sensitive testing which can take between 48 hours and two weeks to provide results.

Engineers have been working alongside opthalmologists at University Hospital Southampton NHS Foundation Trust (UHS), United Kingdom (UK), for tests using laboratory-infected tissue samples and they are now planning to run a pilot study involving 30 patients including tests in Africa and South Asia.

Corneal infections occur when the cornea is damaged by a foreign object and through the growth of bacteria and other micro-organisms – often due to contaminated contact lenses.

There are around 6,000 cases of corneal infections diagnosed in the UK every year, with around a third related to contact lens wear.

Parwez Hossain, a consultant ophthalmologist at UHS, said: “The cornea is only half a millimetre thick and infections can spread rapidly and destroy this structure, so timely treatment is extremely important, but we also have the added complication that treatment can be very different for each type of bacteria present.

“These findings, although currently laboratory-based, could have deep implications for the detection and treatment of corneal infections as it has the potential to reduce diagnosis time from up to two weeks to only a few minutes – and the ability to deliver the correct antibiotics immediately.”

Professor Myron Christodoulides, professor of bacteriology at the University of Southampton, added: “Outside of the UK, rapid detection and targeted antibiotic treatments for eye infections are very urgent needs for many people living in some of the poorest countries in the world.

“We have plans for working closely with our new partners at the Lighthouse Eye Hospital in Kenya and the Christian Medical College in India to use this exciting project to help meet their needs.”